1. Field of the Invention
This invention relates to an improved anchoring arrangement for use in conjunction with cavity walls having an inner wythe and an outer wythe. More particularly, the invention relates to construction accessory devices, namely, specially dimensioned veneer ties with high strength partially compressed pintles and a low profile insertion portion. The veneer ties are for emplacement in the outer wythe and are further accommodated by receptors in the cavity, which receptors extend from the inner wythe to encapture the specially configured veneer ties. The invention is applicable to structures having an outer wythe of brick or stone facing in combination with an inner wythe of either masonry block or dry wall construction.
2. Description of the Prior Art
In the past, investigations relating to the effects of various forces, particularly lateral forces, upon brick veneer masonry construction demonstrated the advantages of having high-strength wire anchoring components embedded in the bed joints of anchored veneer walls, such as facing brick or stone veneer. Anchors and ties are generally placed in one of the following five categories: corrugated; sheet metal; wire; two-piece adjustable; or joint reinforcing. The present invention has a focus on wire formatives and in particular, pintle ties.
Prior tests have shown that failure of anchoring systems frequently occurs at the juncture between the pintle of the veneer tie and the receptor portion of the wall anchor. This invention addresses the need for a high-strength pintle suitable for use with either a masonry block or dry wall construction that provides a strong pintle-to-receptor connection.
Early in the development of high-strength anchoring systems a prior patent, namely U.S. Pat. No. 4,875,319 ('319), to Ronald P. Hohmann, in which a molded plastic clip is described as tying together a reinforcing wire and a veneer tie. The assignee of '319, Hohmann & Barnard, Inc., now a MiTek-Berkshire Hathaway company, successfully commercialized the device under the SeismiClip trademark. For many years, the white plastic clip tying together the veneer anchor and the reinforcement wire in the outer wythe has been a familiar item in commercial seismic-zone buildings. Additionally, the high-strength pintle hereof has been combined with the swaged leg as shown in the inventor's patent, U.S. Pat. No. 7,325,366. The combination item reduces the number of “bits and pieces” brought to the job site and simplifies installation.
The high-strength partially compressed pintle is specially configured to prevent veneer tie pullout. The configured pintle restricts movement and ensures a high-strength connection and transfer of forces between the veneer and the backup wall. The wire formative insertion portion for disposition within the outer wythe, is compressively reduced in height by the cold-working thereof and compressively patterned to securely hold to the mortar joint and increase the veneer tie strength. The close control of overall heights permits the mortar of the bed joints to flow over and about the veneer ties. Because the wire formative hereof employs extra strong material and benefits from the cold-working of the metal alloys, the high-span anchoring system meets the unusual requirements demanded in current building structures. Reinforcement wires are included to form seismic constructs.
There have been significant shifts in public sector building specifications which have resulted in architects and architectural engineers requiring larger and larger cavities in the exterior cavity walls of public buildings. These requirements are imposed without corresponding decreases in wind shear and seismic resistance levels or increases in mortar bed joint height. Thus, the wall anchors needed are restricted to occupying the same ⅜-inch bed joint height in the inner and outer wythes. Because of this, the veneer facing material is tied down over a span of two or more times that which had previously been experienced. Exemplary of the public sector building specification is that of the Energy Code Requirement, Boston, Mass. (See Chapter 13 of 780 CMR, Seventh Edition). This Code sets forth insulation R-values well in excess of prior editions and evokes an engineering response opting for thicker insulation and correspondingly larger cavities.
The use of wire formatives in cavity wall construction have been limited by the mortar layer thicknesses which, in turn are dictated either by the new building specifications or by pre-existing conditions, e.g. matching during renovations or additions the existing mortar layer thickness. While arguments have been made for increasing the number of the fine-wire anchors per unit area of the facing layer, architects and architectural engineers have favored wire formative anchors of sturdier wire. On the other hand, contractors find that heavy wire anchors, with diameters approaching the mortar layer height specification, frequently result in misalignment. Thus, these contractors look towards substituting thinner gage wire formatives which result in easier alignment of courses of block to protect against wythe separation. A balancing of mortar and wire formatives needs to be struck to ensure veneer tie stability within the outer wythe. The present high strength partially compressed veneer tie greatly assists in maintaining this balance in the mortar joint.
Besides earthquake protection requiring high-strength anchoring systems, the failure of several high-rise buildings to withstand wind and other lateral forces has resulted in the promulgation of more stringent Uniform Building Code provisions. This high-strength partially compressively reduced veneer tie is a partial response thereto. The inventor's related anchoring system products have become widely accepted in the industry.
The following patents are believed to be relevant and are disclosed as being known to the inventor hereof:
U.S. Pat. No.InventorIssue Date3,377,764StorchApr. 16, 19684,021,990SchwalbergMay 10, 19774,373,314AllanFeb. 15, 19834,473,984LopezOct. 2, 19844,598,518HohmannJul. 8, 19864,869,038CataniSep. 26, 19894,875,319HohmannOct. 24, 19895,454,200HohmannOct. 3, 19956,668,505Hohmann et al.Dec. 30, 20036,789,365Hohmann et al.Sep. 14, 20046,851,239Hohmann et al.Feb. 8, 20057,017,318HohmannMar. 28, 20067,325,366HohmannFeb. 5, 2008It is noted that these devices are generally descriptive of wire-to-wire anchors and wall ties and have various cooperative functional relationships with straight wire runs embedded in the interior and/or exterior wythe.
U.S. Pat. No. 3,377,764—D. Storch—Issued Apr. 16, 1968 Discloses a bent wire, tie-type anchor for embedment in a facing exterior wythe engaging with a loop attached to a straight wire run in a backup interior wythe.
U.S. Pat. No. 4,021,990—B. J. Schwalberg—Issued May 10, 1977 Discloses a dry wall construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Like Storch '764, the wall tie is embedded in the exterior wythe and is not attached to a straight wire run.
U.S. Pat. No. 4,373,314—J. A. Allan—Issued Feb. 15, 1983 Discloses a vertical angle iron with one leg adapted for attachment to a stud; and the other having elongated slots to accommodate wall ties. Insulation is applied between projecting vertical legs of adjacent angle irons with slots being spaced away from the stud to avoid the insulation.
U.S. Pat. No. 4,473,984—Lopez—Issued Oct. 2, 1984 Discloses a curtain-wall masonry anchor system wherein a wall tie is attached to the inner wythe by a self-tapping screw to a metal stud and to the outer wythe by embedment in a corresponding bed joint. The stud is applied through a hole cut into the insulation.
U.S. Pat. No. 4,598,518—R. Hohmann—Issued Jul. 7, 1986 Discloses a dry wall construction system with wallboard attached to the face of studs which, in turn, are attached to an inner masonry wythe. Insulation is disposed between the webs of adjacent studs.
U.S. Pat. No. 4,869,038—M. J. Catani—Issued Sep. 26, 1989 Discloses a veneer wall anchor system having in the interior wythe a truss-type anchor, similar to Hala et al. '226 supra, but with horizontal sheetmetal extensions. The extensions are interlocked with bent wire pintle-type wall ties that are embedded within the exterior wythe.
U.S. Pat. No. 4,875,319—R. Hohmann—Issued Oct. 24, 1989 Discloses a seismic construction system for anchoring a facing veneer to wallboard/metal stud construction with a pronged sheetmetal anchor. Wall tie is distinguished over that of Schwalberg '990 and is clipped onto a straight wire run.
U.S. Pat. No. 5,454,200—R. Hohmann—Issued October 1995 Discloses a facing anchor with straight wire run and mounted along the exterior wythe to receive the open end of wire wall tie with each leg thereof being placed adjacent one side of reinforcement wire. As the eye wires hereof have scaled eyelets or loops and the open ends of the wall ties are sealed in the joints of the exterior wythes, a positive interengagement results.
U.S. Pat. No. 6,668,505—Hohmann et al.—Issued Dec. 30, 2003 Discloses high-span and high-strength anchors and reinforcement devices for cavity walls combined with interlocking veneer ties are described which utilize reinforcing wire and wire formatives to form facing anchors, truss or ladder reinforcements, and wall anchors providing wire-to-wire connections therebetween.
U.S. Pat. No. 6,785,365—R. Hohmann et al.—Issued Sep. 14, 2004 Discloses side-welded anchor and reinforcement devices for a cavity wall. The devices are combined with interlocking veneer anchors, and with reinforcements to form unique anchoring systems. The components of each system are structured from reinforcing wire and wire formatives.
U.S. Pat. No. 6,851,239—Hohmann et al.—Issued Feb. 8, 2005 Discloses a high-span anchoring system described for a cavity wall incorporating a wall reinforcement combined with a wall tie which together serve a wall construct having a larger-than-normal cavity. Further the various embodiments combine wire formatives which are compressively reduced in height by the cold-working thereof. Among the embodiments is a veneer anchoring system with a low-profile wall tie for use in a heavily insulated wall.
U.S. Pat. No. 7,017,318—Hohmann—Issued Mar. 28, 2006 Discloses an anchoring system with low-profile wall ties in which insertion portions of the wall anchor and the veneer anchor are compressively reduced in height.
U.S. Pat. No. 7,325,366—Hohmann—Issued Feb. 5, 2008 Discloses snap-in veneer ties for a seismic construction system in cooperation with low-profile, high-span wall anchors.
None of the above anchors or anchoring systems provide a veneer tie having a low profile high-strength partially compressively reduced veneer tie for fulfilling the need for enhanced compressive and tensile properties. This invention relates to an improved anchoring arrangement for use in conjunction with cavity walls having an inner wythe and an outer wythe and meets the heretofore unmet need described above.